Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

States of Matter
GASEOUS STATE
Generally four parameters are used to characterise gases : They are
1
...
It is expressed in litre (L), millilitres (ml) or cubic
centimeter (cm3) or cubic meter (m3)
...
The Pressure
It is the force exerted by the gas per unit area of the wall of the container
...

Units :
1 atm
...
I
...
325 × 105 Nm–2 = 101
...

It is also expressed in ‘bar’ 1 bar = 105 Pa
...
The temperature
The temperature is measured either in degree centigrade (°C) or in kelvin (K) with the help of thermometer
...
I
...
The Mass
Mass of gas is expressed in gm or kg or in moles
...


GAS LAWS
(A) Boyle’s Law
At constant temperature the volume of the given mass of gas is inversely proportional to its pressure
...
e
...

Graphical Representation

(i)

(ii)
P

P

V

1/V

(iii)

(iv)
PV

log P

P

logV

(v)

(vi)

T1
T2

P

P

T3

T1
T2
T3
V

1/V
T1
T2

(vii)
PV

P
(B) Charle’s law
This law is based on the observation that for each degree change in temperature, the volume of the gas is
changed by 1/273rd times the initial volume of gas at 0°C
...
If
temperature is increased by t°C the new volume becomes, Vt
...
”
Mathematically
VT

V

or

(if P and ‘n’ are constants)

 constant if pressure and ‘n’ are constants
...



p t
pt  p0  0
273
t 

pt  p0  1 273 

273

of its pressure at 0°C per degree change



where 273 + t = T

273  t
T
pt  p0   273   p0  273



or
P  T
...
e
...





P1
T1



P2
T2

(D) Avogadro’s Law
The volume of same number of moles of all gases measured at constant temperature and pressure are the same
...


V  n at constant T and p

Mathematically

V = k
...
At 0°C and 1 atm the value of k for 1 mole of gas is 22
...

Ideal Gas Law Equation of State
Combination of Boyle’s law, Charle’s law and Avogadro’s law gives the ideal gas equation
...


Charle’s law



V  T if P is constant
...


Thus, V 

nT

i
...
PV  nT
P
Where R is molar gas constant
or



or

PV  nRT

PV  RT for 1 mole of gas

Numerical values of R
(i)

PV
(For one m

---